1. Field of the Invention
The invention concerns mobile phones, in particular portable mobile phones, using a subscriber identification card and in particular those designed to receive commands sent by a service provider in short mobile phone messages, in particular updating commands.
2. Description of the Prior Art
Given the rate of change in fields employing data processing means in particular, it is beneficial for equipment employed by users to be capable of being updated if necessary.
Some methods of operating subscriber identification card mobile phones imply staggering in time of updates to information stored on the cards to the benefit of their users. These updates concern directory information stored in subscriber identification cards for mobile phones of particular interest for a given category of mobile phone users, such as directory information concerning employees of the same company. Such updates staggered in time are also encountered when the cards are used for pre-payment operations implying charging the card with payment units beforehand and recharging the card with such units when the units previously stored have been used up.
Document FR-A-2718263 describes an automatic charging device to which mobile phones are connected to update their control software. A solution of this kind, which may suit some mobile phone operating conditions, is not necessarily practical if the mobile phones are likely to be very widely dispersed geographically. It is efficient only if users can find a charging device within a reasonable distance and if users find the conditions of using any such device acceptable.
Document EP-A-478231 describes a solution to the problem of quickly and efficiently programming a mobile phone using signals transmitted by radio to the radio receiver of the mobile phone from a control center after the user switches the mobile phone to a programming mode to obtain specific mobile service authorization codes. Obtaining these codes is subordinate to the user calling the control center in at least two of the examples described.
Although a solution of the above kind may be suitable in the case of the first entry into service or a request for updating at the initiative of a user, it is not totally satisfactory if the user is not aware that updating their mobile phone is necessary or advantageous.
Commands and information to be displayed can be transmitted to mobile phones using a processor and memory subscriber identification card, and in particular to GSM type mobile phones, via the mobile phone network by a Short Message Service (SMS). The information is to be displayed by the mobile phone and the commands are addressed to a processor, for example the processor on the card. The processor on the card can therefore be used to update the cards, and therefore the mobile phones, via the mobile phone network, as soon as a mobile phone link is set up between a mobile phone and the network. The control structure of the network can be organized in such a way that it is possible to tell if a mobile phone connected to said network has received the updates it needs or not. It is then possible to update the mobile phones of a network automatically as soon as the mobile phones are connected to the network, in accordance with any updates that have come into force.
A solution of the above kind is not without disadvantages, however, given that mobile phones using microprocessor and memory subscriber identification cards as currently on sale generally take account only of information that is present when the respective mobile phones are switched on. This can be very irritating for users who see information displayed that does not correspond to the current situation of the mobile phone displaying the information. For example, if the subscriber identification card of a mobile phone stores prepayment units and if the user has used the mobile phone to carry out a prepayment unit recharging operation, it is possible that the number of prepayment units displayed by the mobile phone after recharging is still the number which would have been displayed before recharging if the mobile phone has not been switched off in the meantime.
Similarly, directory information displayed by a mobile phone may be inaccurate and therefore lead to errors if an update to the subscriber identification card sent by radio was implemented when the mobile phone was already switched on.